Magnet valve safety check and fault indication integrator

Abstract

A magnet valve safety check and fault indication integrator including a first comparator for selecting the highest axle speed of a vehicle, a second comparator for determining whether the highest axle speed is less than a preset speed, an indicator for indicating if the vehicle is stopped, a timer for determining if the vehicle has been stopped for a predetermined time, a first sensor for sensing a transition from a braking mode to a power mode, an inhibit device for inhibiting all magnet valve feedback faults when the vehicle is stopped and in a brake mode for a period longer than the predetermined time, a timer circuit for ascertaining if a wheel slip is not in progress for a certain time period, a check circuit for monitoring the magnet valve feedback to determine if the magnet valve is not in an application state, a magnet valve cutout device for holding a cutout request until it is reset by a station stop signal, an event recorder for indicating that the vehicle speed is not less than the preset speed, a safety timer for designating a wheel slip inhibit in not in effect, a fault sensor for selectively blocking or passing a valve cutout request, an interface circuit for receiving three safety functions, and a code generation circuit for receiving the wheel slip inhibit event, the safety-timer event and the feedback fault for being logged one for every brake to power transition.

We claim: 
     
       1. A magnet valve safety check and fault indication integrator comprising, means for selecting a highest axle speed of a plurality of wheel axle units of a railway vehicle, means for comparing the highest axle speed to a preset speed for producing a logical output signal, means for indicating the vehicle is stopped by comparing the highest speed with a preset speed limit, first means for sensing a transition from a braking mode to a power mode for producing a logical output signal means for timing that the highest speed is less the preset speed limit and in a brake mode for predetermined time for producing a logical output signal, fault code inhibit means being set by the logical output signal of the timing means and being reset by the logical output signal of the transition means, means for determining if a wheel slip condition is absent and for producing an enable signal after a given time, means for checking a feedback state of a wheel slip magnet valve and for monitoring the enable signal for setting a valve cutout means, means for reporting a wheel slip inhibit event when the logical output signal is received from the comparing means and a signal is received from a trainline, means for recording a safety time event, second means for sensing a feedback fault function, and means for causing the wheel slip inhibit event, the safety timer event, and the feedback fault function to be logged for every brake to power transition cycle. 
     
     
       2. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the selecting means is a comparator circuit. 
     
     
       3. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the comparing means is a comparator circuit. 
     
     
       4. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the indicating means is a comparator circuit. 
     
     
       5. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the first sensing means is a monostable multivibrator. 
     
     
       6. The magnet valve safety check and fault indication integrator as defined in claim 5, wherein the monostable multivibrator operates in a flip-flop manner. 
     
     
       7. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the fault code inhibit means is bistable multivibrator. 
     
     
       8. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the determining means is a timer circuit. 
     
     
       9. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the checking means is a flip-flop circuit. 
     
     
       10. The magnet valve safety check and fault indication integrator as defined in claim 1, wherein the means for causing the wheel slip inhibit event, the safety timer event, and the feedback fault function to be logged for every brake to power transition cycle is an OR gate circuit. 
     
     
       11. An electronic wheel slip control system for integrating three wheel slip safety functions for a railway vehicle comprising, a highest axle speed comparator for producing a signal representative of a highest axle speed on the vehicle, a comparator circuit for comparing the highest vehicle speed signal with a preset speed value and for producing a logical "0" when the highest vehicle speed signal is less than the preset speed value and for producing a logical "1" when the highest vehicle speed signal is greater than the preset speed value, a wheel slip inhibit event recorder for producing a logical "1" when a logical "1" is received from said comparator circuit and from a wheel slip inhibit trainline, a final fault code generation circuit for producing a logical "1" for logging the event of said wheel slip inhibit event recorder, a vehicle stop indicator for determining that the vehicle is effectively stopped and is in a brake mode for producing a logical "1", a vehicle stop timer for producing a logical "1" if the logical "1" received from said vehicle stop indicator is present for a predetermined time, a brake to power transition sensor for producing a logical "1" if the vehicle undergoes a brake to power transition during a program cycle, a fault code inhibit set/reset device for producing a logical "1" when set by a logical "1" from said vehicle stop timer and for producing a logical "0" when reset by a logical "1" from said brake to power transition sensor, a timer circuit for producing an enable signal if a wheel slip is not in progress and when said timer circuit reaches a predetermined count, a wheel slip magnet valve application state check circuit for producing an enable signal when conditioned by the enable signal of said timer circuit and is enabled by any magnet valve state other than a brake application mode, a magnet valve cutout set/reset device which is set by the enable signal from said wheel slip magnet valve application state check circuit and which is reset by a signal received from a station stop initiated valve sensor, a feedback fault sensor for producing a logical "1" or a logical "0" in accordance with set and reset conditions of said magnet valve cutout set/reset device and when an input received from said fault code inhibit set/reset device is a logical "0", said final fault code generation circuit producing a logical "1" for logging a fault received from said feedback fault sensor, a safety timer event recorder for producing a logical "1" by a logical "1" received from a safety time cutout sensor until it is reset by a signal received from a wheel slip inhibit trainline, said final fault code generation circuit producing a logical "1" for logging an event received from said safety timer event recorder. 
     
     
       12. The electronic wheel slip control system as defined in claim 11, wherein a magnet valve cutout circuit for receiving a first logic input from said safety time cutout sensor, for receiving a second logic input from said magnet valve cutout set/reset device, and for receiving a third logic input from said wheel slip inhibit trainline. 
     
     
       13. The electronic wheel slip control system as defined in claim 12, wherein said magnet valve cutout circuit is an OR gate. 
     
     
       14. The electronic wheel slip control system as defined in claim 11, wherein said brake to power transition sensor is a one-shot trigger circuit. 
     
     
       15. The electronic wheel slip control system as defined in claim 11, wherein said fault code inhibit set/reset device is a bistable multivibrator. 
     
     
       16. The electronic wheel slip control system as defined in claim 11, wherein said magnet valve cutout set/reset device is a flip-flop circuit.